Appendix B. Coefficients of variation for every subject, describing within subject variance for every variable that was presently measured in the laboratory. These coefficients of variation are quite comparable to previously reported coefficients of variation describing intrasubject variability for forehands performed on an indoor tennis court (Knudson & Blackwell, 2005). HA = Head Angle; VT = Vertical Trajectory Vertical Trajectory; HV = Horizontal Velocity; VV = Vertical Velocity; BI = Before Impact
Subject Hitting Zone Length Racquet HA at Impact (Ëš) Racquet VT
BI (Ëš)		 Racquet HV
BI (m/s)		 Racquet VV
BI (m/s)		 Ball Spin Rate
(RPM)
1 15.9 3.8 18.4 5.0 13.2 9.9
2 19.7 2.5 7.7 9.0 9.7 21.6
3 3.7 2.3 14.2 10.7 21.5 18.5
4 21.9 4.8 14.3 10.8 8.9 21.4
5 16.2 3.2 16.6 7.7 11.3 17.4
6 34.9 2.3 9.8 4.2 7.8 12.1
7 3.6 1.9 7.0 4.1 7.0 22.8
8 10.3 2.8 28.8 6.8 20.8 11.2
9 22.1 2.5 22.3 7.3 25.0 20.6
10 38.0 2.9 14.3 7.0 26.9 7.2
11 34.8 2.5 11.9 6.1 10.0 11.6
12 18.5 3.2 9.6 3.7 6.4 11.5
13 36.1 2.3 18.9 4.8 22.4 7.8
Mean 21.2 2.8 14.9 6.7 14.7 14.9
St Dev 11.8 0.8 6.2 2.4 7.5 5.6